11
STANDARD HEAT TRANSFER SYSTEM TROUBLE SHOOTING CHART
Problem
Cause
Corrective Action
A
Power light off
Main power feed off
Turn on main power
Circuit breaker off
Turn on circuit breaker
Control transformer
Primary fuse blown
Secondary fuse blown
Transformer bad
Replace fuse
Replace fuse
Check and/or replace
Pilot light blown
Replace bulb
B
Power light on, pump will not start
Float switch open
Add fluid to system, If no float switch, jumper terminals 4 & 5
Motor overloads tripped
Reset overloads, check running current
Motor starter bad
Check motor starter coil
C
Power light on, pump light on, mo-
tor not running
Motor fuse blown
Replace fuse, check motor overloads
Motor burned out
Replace motor, check motor for overload
D
Power light on, pump light on, mo-
tor running, pump not running
Broken coupling
Check and replace coupling
Pump jammed by slag or foreign ob-
ject
Turn off system and rotate pump by hand if jammed, disas-
semble and clean pump. Check and clean strainer.
E
Power light on, pump light on, mo-
tor running, pump running heat will
not come on
Heat on-off switch in off position
Turn switch to on
Process control set too low
Set process control to desired temperature
F
Insufficient heat
No flow
See items: pump noisy, see L; insufficient suction pressure,
seaI; high discharge pressure, see J
Process piping too small or restricted Check process piping, check heat transfer area of platen,
etc.
Heater fuses blown
Check and replace fuses
Heater elements burned out
Check continuity and resistance of elements
G
System leaks when filling
Rough handling during shipment
Check piping and flange alignment retighten and torque all
bolts to specifications
H
System leaks at temperature and
after cool down
Expansion and contraction due to
temperature has loosened connec-
tions
Check all flange bolts and connections retighten and torque
to manufacturer’s specifications
Wrong gasket materials
Replace gaskets as necessary.
I
Insufficient suction pressure (0 or
vacuum), pump noisy, gauges vi-
brating, discharge pressure low
(below 20 psig)
System temperature too high causing
vapor lock
See fluid manufacturer’s data for maximum fluid temperature
Vapors lock due to air in system
Bleed air from system
Net positive suction pressure too low Raise expansion tank to increase suction head, static head
should be 4-5 psig.
Strainer plugged
Remove and clean strainer
Valve closed
Check all valves
J
High discharge pressure over 40
psig, pressure gauges fluctuating
rapidly, pump noisy, expansion
tank normal, system operating on
bypass relief valve
System piping blocked or restricted
Check all valves, check strainer
Process piping blocked or restricted
Check process piping sizing, check for closed valves or im-
properly installed automatic valves, check all bleed valves
for air or steam
K
Expansion tank overflows or
“burps” (over 220°F)
Expansion tank too low
Expansion tank should be mounted 15 ft. above system
Expansion tank line too short
Lengthen expansion tank line to cool fluid and provide cold
seal
Tank too small for system
Check volume on process piping
L
Pump noisy and/or cavitation
Air in system
Bleed system periodically until all air is removed
Insufficient bleed valves in process piping to remove trapped
air
Pump damaged by overtightened
packing gland
Replace pump
Insufficient suction pressure
Suction pressure should be 4-5 psig